Compressed powder metal bullets are bullets comprised of powdered metal that are made using powdered metallurgy techniques. Such techniques include compressing powdered metal to form a green solid, then subsequently heat treating to obtain a desired metallurgical strength. These bullets can then be jacketed, plated or made to size in a centerfire or rimfire cartridge. Bullets made from compressed metal powder can be made “frangible” by altering the process to achieve a brittle microstructure. Such bullets are characterized by the use of metal powder consolidated into a bullet that has sufficient strength to maintain its integrity during firing while fragmenting on impact with a solid object.
Unlike, conventional, full-density, cast, swaged, copper plated or copper jacketed lead bullets, frangible bullets protect the shooter from ricochets. For this reason, the walls of traditional shooting ranges were often covered with a projectile absorbing material, such as rubber. In addition, shooting lead bullets necessarily causes the emission of airborne lead dust, which not only requires the implementation of elaborate ventilation systems in shooting ranges, but the proper disposal of spent lead bullets and bullet fragments. Government regulations on the use and exposure to lead are making it a banned element in bullets. Recently, the state of California has banned hunters from using lead bullets.
In view of these problems, there has been a long-standing search for a material to use as a bullet that does not contain lead and does not ricochet. One problem in replacing lead in ammunition is that the replacement material must be sufficiently heavy such that ammunition using such bullets, when used in automatic or semi-automatic weapons, will be able to cycle the weapon properly. Further, a lead-free, training round should break up into small particles when it hits a hard surface, such as when used for low costs “plinking” rounds. The individual particles are then too light to carry enough energy to be dangerous.
One problem associated with the use of frangible bullets is that typically do not exhibit appropriate ductility for use in large scale manufacturing. Traditional powdered metal projectiles are too brittle to withstand the forces that allow them to be loaded and crimped into a cartridge and subsequently chambered, fired and ejected from a rifle corresponding to its caliber.
The disclosed bullet is directed to overcoming one or more of the problems set forth above and/or other problems of the prior art, specifically providing beneficial ductility properties that allow it to withstand crimping and high volume production using existing capital and tooling.